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One thermostat for pellet and oil question

jmansfield04 Member Posts: 1
Hey everyone! New to the forum first post.

Hoping someone can help me with this question. I have a Quadra fire pellet stove and an oil boiler for heating my home. When oil is cheap I run the boiler and when it's expensive I use pellets. I've been using one thermostat which is centrally located in the house and manually connecting the tstat wires to the unit I want to use for heat. This has been working pretty well however there are times I would like to easily switch the thermostat from one unit to the other without moving my thermostat wires. My question is, how would I connect a switch so I could easily toggle the tstat between the two units? My thermostat wires are two wire. My thinking is that I could use a SPDT switch but I may be way off on that. A wiring diagram would be most helpful!



  • bmwpowere36m3
    bmwpowere36m3 Member Posts: 512
  • SWEI
    SWEI Member Posts: 7,356
    You could also install a two-stage stat.
  • Solid_Fuel_Man
    Solid_Fuel_Man Member Posts: 2,646
    With what you are saying a DPDT switch is what you need. A two stage would be for just one source of heat being primary (pellets) and the second being backup (oil). To simply toggle between two the DPDT switch and the single stage thermostat that you already have is good.

    Two position DPDT will have 6 leads, the two center go to the thermostat, and two on one end go to oil, and the two on the other go to pellets. The switch is now doing exactly what you have been doing, switching both wires to the thermostat. Something like a snow plow light toggle switch at the automotive store is what you want.

    Serving Northern Maine HVAC & Controls. I burn wood, it smells good!